If there is a reaction mixture in an organic solvent that contains an organic acid, an organic base, neutral organic compounds, and base containing impurities, what is in the aqueous layer after complete treatment with naoh(aq)?

Answer is: organic acid will be in aqueous layer after treatment with sodium hydroxide.
An organic base, neutral organic compounds and base containing impurities will not change polarity with reaction with sodium hydroxide (base) because they not react with bases. Organic acid reacts with sodium hydroxide and change polarity because releases proton and become salt that dissolves in water. Other molecules are dissolved in nonpolar organic layer.

The simplest and most helpful visual aid for this experiment would be if the student sets rulers of some sort or maybe pieces of wood that are properly marked with certain measuring unite. If they are set right next to each plant, the student will be able to monitor constantly how are the plants growing, and the smaller the measuring unites the better, as the student will be able to monitor the situation in higher detail.

Over time, the plants will most surely develop differently, so the student will have it easier to notice the changes. Considering that it is an experiment in question, the student should use proper measurements and to be able to have detailed numbers for it.